[APP-9815] Part 2: Viam Mobile - Displaying sensor data improvements (#457)

* create scrollable

* add no sensors readings when none

* fix and add test

* Wait for async getReadings() to complete

* add padding

Author: jckras

lib/widgets/refreshable_data_table.dart

@@ -99,9 +99,31 @@ class _ViamRefreshableDataTableState extends State<ViamRefreshableDataTable> {
   Widget build(BuildContext context) {
     return Column(
       children: [
-        DataTable(
-            columns: const <DataColumn>[DataColumn(label: Text('Reading')), DataColumn(label: Text('Value'))],
-            rows: readings.keys.map((e) => DataRow(cells: [DataCell(Text(e)), DataCell(Text(readings[e].toString()))])).toList()),
+        if (readings.isEmpty)
+          const Text('No sensor readings available')
+        else
+          DataTable(
+              columns: const <DataColumn>[DataColumn(label: Text('Reading')), DataColumn(label: Text('Value'))],
+              rows: readings.keys
+                  .map((e) => DataRow(cells: [
+                        DataCell(Text(e)),
+                        DataCell(
+                          SizedBox(
+                            width: MediaQuery.of(context).size.width * 0.5,
+                            height: 120,
+                            child: Align(
+                              alignment: Alignment.centerLeft,
+                              child: SingleChildScrollView(
+                                child: Padding(
+                                  padding: const EdgeInsets.all(8.0),
+                                  child: Text(readings[e].toString()),
+                                ),
+                              ),
+                            ),
+                          ),
+                        )
+                      ]))
+                  .toList()),
         if (widget.showLastRefreshed && lastRefreshed != null)
           Column(children: [
             const SizedBox(height: 8),

test/widget_tests/refreshable_data_table_test.dart

@@ -10,12 +10,26 @@ void main() {
     testWidgets('displays data', (tester) async {
       final widget = TestableWidget(child: ViamRefreshableDataTable(getData: FakeSensor('sensor').readings));
       await tester.pumpWidget(widget);
+      await tester.pumpAndSettle();
 
       final dataTable = find.byType(DataTable);
 
       expect(dataTable, findsOneWidget);
     });
 
+    testWidgets('displays no sensor readings available', (tester) async {
+      final widget = TestableWidget(
+        child: ViamRefreshableDataTable(
+          getData: ({Map<String, dynamic>? extra}) async => <String, dynamic>{},
+        ),
+      );
+      await tester.pumpWidget(widget);
+
+      final noSensorReadingsAvailable = find.textContaining(RegExp(r'No sensor readings available'));
+
+      expect(noSensorReadingsAvailable, findsOneWidget);
+    });
+
     testWidgets('shows last refresh time', (tester) async {
       final widget = TestableWidget(child: ViamRefreshableDataTable(getData: FakeSensor('sensor').readings, showLastRefreshed: true));
       await tester.pumpWidget(widget);